Re: git-svn doesn't recognise trunk as parent of branch

On Sun, Apr 12, 2009 at 07:40:46PM +0300, Orestis Markou wrote:

Hello there - this is my first post to this ML, so please be kind!

I have previously used git-svn with great success. However, in this  
project, the svn repo layout is a bit unusual and I'm having getting  
git-svn to do the correct thing.

The repository I'm trying to clone is a subdirectory under a huge repo:

http://svn.example.com/projects/trunk/MyProject/Production

which has trunk, branches and tags and a couple of other directories  
(which I'm not interested in).

Complications so far:

* I don't have read access to the lower directories, only to Production
* Being a part of a big repo, the initial revision is something like  
2000
* trunk, branches, tags where not created in the same revision. trunk  
didn't exist until revision say 2050.


Doing 'git svn init -s 
http://svn.example.com/projects/trunk/MyProject/Production' produces the 
following configuration:

[svn-remote "svn"]
url = http://svn.example.com/trunk/projects/MyProject/Production
fetch = trunk:refs/remotes/trunk
branches = trunk/projects/MyProject/Production/branches/*:refs/remotes/*
tags = trunk/projects/MyProject/Production/tags/*:refs/remotes/tags/*

Fetching this fetches only trunk and no branches.

Amending the config to be:

[svn-remote "svn"]
	url = http://svn.example.com/trunk/projects/MyProject/Production/
	fetch = trunk:refs/remotes/trunk
	branches = branches/*:refs/remotes/*
	tags = tags/*:refs/remotes/tags/*


and fetching (minor issue - have to start from scratch again), does  
fetch all commits. However, there is no link between branches and trunk. 
Using gitk (don't know how else to visualise this) shows branches as 
having no parent. Indeed, in the fetch messages there is no 'found 
possible parent' message. Also, when creating new branches in svn, 
nothing shows up in git until a change happens. Then the branch is 
created (again, with no parent).

The only case where a correct parent was set was when someone branched  
*from a branch*. Then the usual 'found possible parent' message  
appeared, and gitk shows a sane tree.

I'm on Mac OS X, git version 1.6.2.2.471.g6da14 (built from source,  
master branch). This includes a recent commit that fixed an issue with  
deep directories in git-svn, (without it I couldn't get the branches  
anyway), but it doesn't seem to have fixed the problem completely.

Any pointers welcome.

It might be that git svn can't work with this strange repo or with trunk
created after the branches (no idea if this is a bug or intentional), but I'll
show you a easy way how to fix the git repo after the import by using grafts.

If you have a wrongly connected development (which you are trying to fix) line like
the following example:

Time goes from left to right

	1 - 2 - 3 - 5 - 6       branchA

       	        a - b - c - d   trunk

you could fix it by connecting the graph using

	echo a 2 >> .git/info/grafts

to get something like this

	1 - 2 - 3 - 5 - 6       branchA
	      \
       	        a - b - c - d   trunk

Replace 'a' and '2' with the sha1 value of the corresponding commit. The same
way you could teach git about merges in svn. To make the changes permantent,
use something like

	git filter-branch --tag-name-filter cat -- --all

(Pls. check the manpage, I'm not that familiar with git filter-branch)

-Peter